roleoption: fix error message for SUBJECT option

[rafiss]

The string formatting logic was incorrect before.

fixes #123062
Release note: None

[cockroach-teamcity]

This change is 

[souravcrl]

LGTM.

[rafiss]

tftr!

bors r+

[craig]

Build failed:

• examples_orms

[rafiss]

bors retry

[craig]

Build succeeded:

• linux_arm64_build
• unit_tests
• check_generated_code
• macos_amd64_build
• acceptance
• local_roachtest_fips
• windows_build
• examples_orms
• linux_amd64_fips_build
• linux_amd64_build
• lint
• local_roachtest
• docker_image_amd64
• macos_arm64_build

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error setting reviewers, but backport branch blathers/backport-release-24.1-123063 is ready: POST https://api.github.com/repos/cockroachdb/cockroach/pulls/123072/requested_reviewers: 422 Reviews may only be requested from collaborators. One or more of the teams you specified is not a collaborator of the cockroachdb/cockroach repository. []

Backport to branch 24.1.x failed. See errors above.

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